In a belt-type grinding machine, the shoe which holds the abrasive belt in contact with a part being ground often has a replaceable, hardened nose piece. The nose piece is generally T-shaped having a cross member provided with opposite side portions and a stem between the side portions. The head has a stem-receiving recess and outwardly facing locating shoulders on opposite sides of the recess. The nose piece is mounted on the head with the stem in the recess and the side portions of the cross member overlying the shoulders. In the past, the nose piece has been fastened to the head by conventional screws which clamp it against one side of the head rather than down firmly on the locating shoulders. As a result, the nose piece may tip slightly, resulting in imperfectly ground parts.
In accordance with this invention, releasable retainer means are provided to secure the nose piece on the head comprising a pin received in aligned openings in the head and in the stem. The pin has means for forcing the stem into the recess and forcing the side portions of the cross member down squarely and solidly upon the shoulders.
More specifically, the pin has a flexibly resilient shank extending through the openings, and the shank is provided with a lateral offset in the stem opening. The pin is rotatable to a locking position in which the offset presses inwardly on the stem opening to force the side portions of the cross member firmly into bearing engagement with the shoulders. In one embodiment of the invention, the shank has a laterally bent portion providing the offset. In another embodiment, the shank has a projection on one side providing the offset.
One object of the invention is to provide a nose piece retainer having the foregoing features. Further objects are to provide a nose piece retainer which is of relatively simple construction, rugged and durable in use, and easy to manufacture and assemble.
Other objects, features and advantages will become more apparent as the following description proceeds, especially when considered with the accompanying drawings.